Only 30 of the 90 people charged in a government offensive against alleged price-gouging by retailers remain in custody, Venezuela's attorney general said Friday.

The other 60 people arrested in the operation were granted pre-trial release, Luisa Ortega said in an interview with Venevision television.

The AG's office has opened 104 criminal investigations since President Nicolas Maduro launched the "fair prices" campaign a month ago, she said.

"We have observed with much satisfaction that some of those merchants that had fallen into irregularities have been making corrections to their business approach, that is, without speculation, without usury, without hoarding," Ortega told the network.

Accusing some big retailers of "looting" the country with markups as high as 1,000 percent, Maduro ordered a "grand national civic-military operation" to impose fair prices.

The leftist president and his party say that while retailers import products using foreign currency provided by the government at the official exchange rate of 6.3 bolivares to the dollar, they set their prices based on the black-market rate of 63 bolivares to the greenback. EFE